Therefore, these products with defined 5' and 3' ends accumulate exponentially with each round of DNA amplification -- that is, for every n cycles of PCR there will be 2 -fold amplification of the specific DNA fragment.
1 By themselves, PVCâs do not present any problem.  Bigeminy, Trigeminy, Quadrigeminy, etc. - ventricular bigeminy is the occurrence of a PVC every other beat, trigeminy is every third beat, quadrigeminy every fourth beat. The main point with these types is that the PVCâs are more frequent in these circumstances. They are otherwise little different from PVCâs.
Also referred to as Trisomy 21, Down Syndrome is a genetic condition in which there is the presence of all or part of an extra 21st chromosome. Causing lifelong developmental issues and mental retardation, Down Syndrome is also characterized by specific physical features such as a flat face or a shortened neck.